He wrote: “These are the highest windspeed forecasts I've ever seen in my 10 yrs of Atlantic hurricane forecasting.

“Irma is another retiree candidate.”

Mr Ventrice said he hoped the incredible speeds had been over-estimated and the storm would not be as potentially devastating as it appeared.

But he admitted the outlook was “scary” and, if the data was correct, Irma could rival Hurricane Allen in 1980 for record speed.

Allen, which struck the Caribbean, parts of Mexico and southern Texas, reached Category 5 status and has been designated one of the strongest hurricanes ever recorded.

It killed 290 people and huge damage as it swept along.

Although Irma showed signs of slowing on Friday, Mr Ventrice said it had begun intensifying again and its eye was expanding.

National Hurricane Centre forecaster Eric Blake said: “An upper-level low will be dropping southward on the east side of that high, and should be a key feature to how far south Irma goes before eventually turning westward and west-northwestward early next week.”

On Wednesday morning, Irma was designated as a tropical storm but has already been upgraded to a Category 3 hurricane, with speeds of 115mph.

Hurricane Harvey's catastrophic destruction

Sat, September 2, 2017

Hurricane Harvey was the first major hurricane to make landfall in the United States since Wilma in 2005